Electrical measuring instrument.



gheny and State CLARENCE `iiisonnin,y or PITTSBURGH, AND WILLIAM TUBINGCOMPANY,

A. CORPORATION OF PENNSYLVA IVI. BURG,` PESYLVANIA, ASSIGNORS TOWESTINGHOUSE BRADSHAI/V, OF 'WILKINS- ELECTRIC AND I'IANUFAC- NIA.

ELECTRICAL MEASURING INSTRME'T.

Application filed September 10, 1915.

To all whom if may concern:

Be it known that we, CLARENCE A. Bonnin a citizen of the United States,and a resident of Pittsburgh, in the coun t-y of Alleof PennsylvaniaYand VIL- LnxM M, BimnsiiAw, a citizen of lthe United States, and aresident of Wilkinsburg, in the county of Allegheny aiid'State ofPennsylvania7 have invented a iiew and useful Improvement in ElectricalMeasuring Instruments, of which the following is a specification. l*

Oui' invention relates to electrical measuring instruments andparticularly to motor meters.

The object of our invention is to provide an instrument of the aboveindicated character that is small in dimensions and eco.` noniical tomanufacture and that operates correctly on a wide range of load.

Heretofore, various methods have been proposed tor straightening theload curves of alternating current watthour meters. One of these methodsconsists in increasing the torque ot' the meter at high loads so as toovercome the increased retarding effect of the current winding. In ourpresent invention we provide means for decreasing the retarding' effectof the current windings without aii'ecting the torque of the meter andthus obtain a substantially straight load curve of constant value over awide range.

We have discovered during the course of our experiments that in awattmeter having two polar projections, upon which the cur' rentwindings are wound, when the projections are located close together theretarding etl'ectI produced on the armature by the said current windingsis greater than if the two polar projections are disposed arelativelygreat dist-ance apart. We have, ac cordingly, made practical applicationof our discovery in the presentmeter ,fin which a single polarprojection'tor the series'or current winding is provided, the reta-rdingef, feet of the current winding being thereby reduced as well as thecost of manufact-ure.

In tlieaccoinpanying dra :ings Figure l is a front elevational View ofan electrical. measuring instrument embodying our L'invention; Fig. 2 isa side'view, partially in elevation and partially in section, of theinstrument shown in Fig. 1; Fig. 3 is a diag aromatic view of aninstrument embodying Specication of Letters Patent.

rammen Nov. se, raie.

Serial N o.

i our invention; Fig.- d is a diagram illustrating lthe per cent.

registration curve for vari-A ous-.loads traversing an instrumentenibodving our invention,

view

of the light-load adjusting instrument show and Fig. 5 is a detaileddevice ot' an nin Figs. 1 and 2.

magnetic supporting member 2 is attached by screws 2tL to two bracketsQ" that are mounted on the inner walls of a meter casing l. i

The magnetic ,v l supporting member 2 has atnism 7.

The casing l is provided with a tei'- .ininal block ,8 and with acover-9 having an opening 10 therein for the purpose of observing thepointers (not shown) that are attached to the' integrating mechanism 7.

The magnctizable prises a main body projections 12 and core member 3'comportion 11 and two polar 13. The polar projections 12 and 13 aresubstantially parallel and are separated by a vsingle pole faces l2'nland 13a and 15 are enlar air gap 14.. The of the projections 12 ged forthe purpose ot' more uniformly distributing the magnetic flux.

An armature 15 is disposed in an mounted on a shaft 16 and air gap 17between the magnetizable member 4 and the pole't'aces 12a and 13a.nected through grating mechanism 7.

The shaft 1G is operatively cona gear train 18 to the inte- A potentialwinding 19 surrounds the main body portion 11 of the member 3 in such amanner that the polar and 13 will be of opposite A current winding 2Osurrounds the projections l2 signs.

polar projections 12 and 13 and spans the air' gap 11i, and causes themagnetic tiux produced 13 to be ot' the short-circuited polarprojections 12 through the air 'correcting the operation for changes inpower factor. ing member 22 is disposed iii the air :t'or the purposestarting torque The conductor 2Q is is also lprovided thereby in thepolar projections 12 and same sign. A ligure eight winding 21 surroundsthe and 13 and passes gap 14, for the purpose of of the instrument A datconducti gap 17 of adjusting the light load of the instrument.

that are slotted for the re- W2C.' The ear 25 with a toothed rack 27that provided with opcn-' ings and with two angular projections orearsQL and ception of adjusting screws lines of? forme that ere producedby the is engeged by a, gem* wheel 28 whereby the eonduetor 2.9L may beadjusted. beek and forth the :l gap l?. The, gem? wheel Q8 is mounted e;pin baring e slot in' its outer 'eind tolirfapt it to be turned 'bj/.fat screw ble Gore, member 3. ture 1s cut by magari' tbe potentielsl/Lim'lingfs, and smc; these exes produce eddy currents in the myn'ltture 15, the ermzztm'e ie caused to ro .e e substantially ,inproportion to the product et tbe two flume." Wever; since the er i'eture rotet we lite-poles of the per# marient magnet-e 5 end t :2ndbetween tbe pole, projection? it will l retej e p will be node/retos thepolar prei nl, e polar projet the Current windi and, hence, the tionder: to tbe ect;l n ot' 'tbe eddy mira" in' the armature u the Currentwindu tlftn it would beit t were used, haring ont 'the retardation ofrelatively 's e str those x ,os 15.2 :and U5 zlly polar projectionspoteri ,v'. Hence,v le such that ne of smbstmrtzllly con- 'mfn our"nvsmton in will be umlerstoszrl f" may l aule ther "no the epi''t andSeope iortl'n n the epgllendeil er; our in n'aeeeirng instrument Itizable bore member "ated by n. s" ole me rer that if; me

time the core member l i'. weed :edjecent to the p `les.,a` poel windingdisposed on the Core. :n @ma fling f lepesed :around the'y poles :mdutp? :md :u1 :rrnmt re disjjwoeed :sf-

Y, l' @initially e ar mpx produced by the winding if@ 13 and tbe-memberl# with resp'l-et to tbe tuoi produced by Lne reggmtretlon jacent thepoles, a non-magnetic support for magnetically separa-tung themegnetrzable member from the core member, a current Winding disposederound the poles and the separated lby e. single. zrr gap, amagnetizable member that is megnetlcally seperated from the eore memberand disposed adjacentA the poler projeetione, means for producing fluir.ofthe seme signet the two polar protoneend anarmeturedisposed betweenthe polar projeetone :and the megnetzable member e. plane riglrt anglesto the plane of 'tbe mtr gap. I

4. l motor ernprieing a magnetizable core member lmfvine; twosubstantially parallel poles seperated, by e. single air gap, :marmature disposed adjacent the poles', u potentiel Winding disposed onthe vcore, a current winding so disposed varound both ofthe poles :ltsto produee magnetic lines of flux oit' the seme signtlrereln, und amegnetizable .neamber' dispoeed adjacent the' poles and gnetnetrceltyseperated from the core member. j j

An electrical' meesurng instrument wmp t'. 'ing e. megnetzeble coremember lmvng; two eubetentelly parallel poles seperetedgby e, relativelysmall eir gap,.a mag-f nel tble member that ifs-magnetically sepam fromthe eorehmember and disposed adjacent the. poles, e disk rmaturedisposed between' the' petes' end the magnetxzeblke member, at potentielWmdmg dlspose'd on the vcore member and adapted .to produce nuag- ?.5ndfrp ed to decrease the retarde "from of the armature.

t5. fr, motor comprising a, magnetizuble 4cora-l 'member having twopoles separated by s nigle air gup.- e .megnetzn/ble member magnetically.seperated from the core Aaber md that is (ilitposedl edjacent the endeof thermales, an armature disposed between the poles nd the nmgnetizablemember, e potentiel winding' adapted to produce .nx of opposxte slgn 1nthe poles,

ent winding; adapted to produce f o the saune .sign in the poles. 11testimony whereof we have hereunto -znbse1ilwerl our names this 8th dayof Sept.,

ISM..

. RADS'NW.

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